"When a vagrant--the Walking Man--finds a dog wandering alone with a scrap of paper with the words "HELP US" attached to its collar, he's sure it's a desperate plea from someone in trouble and calls on Detective Inspector Jack Caffery to investigate. Caffery is reluctant to get involved--until the Walking Man promises new information regarding the childhood abduction of Caffery's brother in exchange for the detective's help tracking down the dog's...